We know that Bethesda wants to make QuakeCon bigger. So I ask myself this question: "How much more media attention would QuakeCon get this year without a TES announcement, as compared to previous years?"
Not much more I don't think. West and Vampella will certainly draw a crowd, but they're not going to announce anything substantial. I think the key thing to consider is that Zenimax and id and Bethesda aren't just trying to make QuakeCon bigger, they want to make it more
relevant. They want gamers and game journalists to get excited about it and they want to broaden the potential audience that might come to this thing. Previously, the public perception of QuakeCon was that it was a place people go to play Quake, and where id occasionally announces some cool stuff.
Occasionally. If Bethesda and their partners make announcements there, then QuakeCon ceases to be the "Quake and Doom Show" and becomes something much larger, and broader, with a hell of a lot more reach.